This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The objective of these studies is to further the development of topical microbicides aimed at the prevention and control of sexually transmitted infections (STIs) through preclinical testing in nonhuman primates (NHP), utilizing our established models for topical microbicide safety and efficacy evaluations. Macaque models of Chlamydia trachomatis and Trichomonas vaginalis are currently available for efficacy studies in this laboratory. All test products, provided by NIAID, will first complete safety evaluation with repeated intravaginal or intrarectal product application. Products with acceptable safety profiles may be enrolled (with NIAID approval) to efficacy studies involving one or more STI. Safety measures include microbiologic and pH assessments and documentation of mucosal tissue responses as evidenced by colposcopic evaluation or rectal lavage assessment. Efficacy is determined by a product's ability to prevent infection by the challenge pathogen.